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Investments - Narrative (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) security | Dec. 31, 2023 USD ($) security
Investments, Debt and Equity Securities [Abstract] |  |
Vertical risk retention interest | 5.00% |
Trading investments | $ 54,840 | $ 54,481
Number of government sponsored securities with unrealized losses | security | 194 | 213
Number of mortgage-backed securities | security | 278 | 248
Par value of mortgage-backed securities pledged to FRB | $ 610,000 | $ 612,000
Non-marketable securities investment | 24,000 | 14,000
Low income housing tax credit investments | 84,000 | 72,000
Liability for unfunded commitments | 33,000 | 30,000
Low income housing tax credit investments, tax credits and benefits (less than) | $ 2,000 | $ 11,000
Low income housing tax credit investments, expected tax benefits recognized | 25.00% |

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- Definition Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 323 -SubTopic 740 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/323-740-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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